4.10.2 - Life cycle assessment and recycling

Why are life cycle assessments carried out?

To assess the environmental impact of products.

What stages of a products life are assessed in a life cycle assessment?

• Extracting and processing raw materials (+transport and distribution)

• Manufacturing and packaging (+transport and distribution)

• Use and operation during its lifetime (+transport and distribution)

• Disposal at the end. (+transport and distribution)

Carry out an LCA for a paper shopping bag:

• Raw materials: recycled paper or cutting trees. Making paper requires more energy that recycling paper but cutting down trees contributes to deforestation and reduced 02 levels.

• Manufacturing: pulping paper uses lots of energy and produces lots of waste

• Usage: not very durable therefore normally single use meaning doesn’t last very long.

• Disposal: can biodegrade or can be recycled, both environmentally friendly.

Carry out an LCA for a plastic shopping bag:

• Raw materials: plastic comes from crude oil which is a finite resource and requires a lot of energy to process.

• Manufacturing: Fractional distillation, cracking and polymerisation, fairly cheap and not much waste produced however it takes up lots a of energy to carry out those processes which are fuel by fossil fuels, producing greenhouse gases.

• Usage: Durable and reusable, therefore a long usage life.

• Disposal: Can be recycled but it is expensive and produced pollution. Can be stored in landfill however it takes up space, is an eyesore, isn’t biodegradable and can pollute waters.

Advantages of recycling?

• decreases landfill waste

• reduces the use of finite resources

• economically beneficial to recycle materials and not as much energy is needed

• Mining and extracting ores is very bad for the environment.

Disadvantages of recycling?

• workers are needed to sort through materials which requires lots of energy and labour.

• Collection and transportation requires energy and fuel.

• Sometimes recycled materials aren’t of the same quality.

How is glass recycled?

Crushed and melted to be molded into different products.

How is metal recycled?

Melting, recasting or reforming into different products, may need to be separated to extract different metals from alloys/compounds.